Ball-caster



(No Model.)

J. C. WBIR. BALL GASTER.

Patented July 2, 1889.

mail

InUEnm? Tf1/MESE, e5.'

UNITED STATES yPATENT OFFICE.

JAMES C. IVEIR, OF SAN FRANCISCO, CALIFORNIA.

` BALL-CASTER.

SPECIFICATION forming part of Letters Patent No. 406,185, dated July 2,1889.

Application tiled September 4, 1888. Serial No. 284,584. (No model.)

To all whom, it may concern:

Be it known that I, J AMES C. WEIR., a citizen of the United States,residing in the city and county of San Francisco, and State ofCalifornia, have invented certain new and useful Improvements in.Ball-Casters for Furniture, of which the following is a specification.

My invention relates to ball-casters for furniture, trunks, and othermovable articles; and it consists in a certain novel construction andcombination of parts, as herein after fully described, and pointed outin the claim.

Referring to the accompanying drawings that form a part of .thisspecification, Figure 1 represents the caster applied to the leg of apiece of furniture. Fig. 2 is a vertical section, on a larger scale, ofthe ball-socket with the ball in place. Fig. 3 is a bottom view of thesocket with the ball removed. Fig. 4 is a cross-section taken centrallythrough the half-spherical socket. Fig. 5 shows the rollerbearings indetail, and Fig. 6 shows the bottom plate in section. Fig. 7 shows oneof the bearing-rollers in section.

The same letters of reference are used to denote corresponding partsinthe several iigures.

The half-spherical socketA is provided with a flange a, and the bottomplate B, corresponding in diameter with the socket-flange, fits closelyupon it, so that the screws S S serve to hold the bottom plate, as Wellas to secure the socket in place. Bearing-points for the ball C areformed of a number of rollers D DX, that are arranged in two sets in thesocket, one above the other. The rollers of each set are strung' on ahoop or ring E of cylindrical Wire, on which they are mounted to turnloosely and also to slide longitudinally, and the two sets formed in thesame manner, except that the lower set, being located at the bottom ofthe socket, has its ring of larger diameter than the one that carriesthe upper set of rollers. The interior of the socket is divided intoseveral recesses a2, of uniform size, by means of the radial ribs A3 A3,that extend from the crown down to the flange, and the cavity being madesufcientlylarger than the ball C for this purpose, the edges of the ribsclear the surface of the ball. These ribs serve the double purpose ofspacing the rollers and furnishing supporting-points for the rings.Notches EX are cut in the edges of the ribs to receive the rings, and atthese points around the circle each ring is held out y at suitabledistance from the interior surface of the socketfcavity to keep therollers clear and cause them to turn freely, While the rollersthemselves are of suitable diameter to bear on the surface of the balland keep it clear of contact at all points within the socket. As thusconstructed and arranged, the rollers are free to slip on the rings E,as well as to rotate under the various motions of the ball, but theslidin g movements are limited by the ribs A3, so that the rollers areseparated and properly spaced to distribute the bearing-points equallyaround the ball during-all its motions in the socket.

A caster constructed in this manner can be made exceedingly light', andyet capable of sustaining considerable weight.

Having thus fully described my invention, what I claim, and desire tosecure by Letters Patent, isf The herein-described ball-caster, consstiu'z of the socket A, having the separate internal recesses a2 and theange a, the bottom plate B, ball C, and the bearing-rollers D DX,mounted on hoops E, all constructed and combinedv for operation as setforth.

In testimony that I claim the foregoing I have hereunto set my hand andseal.

JAMES C. WEIR. [L s] Witnesses:

C. W. M. SMITH, JOSEPH E. FORD.

